Goodwill and Intangible Assets - Schedule of Intangible Assets and Goodwill (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Goodwill And Intangible Assets [Line Items]
Goodwill	$ 44,126	$ 28,810
Finite-Lived Intangible Assets, Gross Carrying Amount	31,275	27,831
Finite-Lived Intangible Assets, Accumulated Amortization	(11,623)	(10,110)
Finite-Lived Intangible Assets, Net Carrying Amount	19,652	17,721
Core Deposit Intangibles
Goodwill And Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross Carrying Amount	29,511	21,825
Finite-Lived Intangible Assets, Accumulated Amortization	(11,335)	(8,423)
Finite-Lived Intangible Assets, Net Carrying Amount	18,176	13,402
Other Intangible Assets
Goodwill And Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross Carrying Amount	1,764	6,006
Finite-Lived Intangible Assets, Accumulated Amortization	(288)	(1,687)
Finite-Lived Intangible Assets, Net Carrying Amount	$ 1,476	$ 4,319

Goodwill and intangible assets.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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